The duchy of Normandy was originated from the county of Rouen, which was
given to the Viking chieftain Rollo as a French fief from the king Charles
the Simple 911. The county expanded during the 10th century and got the name
Normandy after the French word for Viking. The title duke is known to have
been used by the rulers since 1006. Sixty years later was England conquered
by the duke of Normandy. The union with England lasted with a short break until 1204 when Normandy
was conquered by the French king and became a part of their royal domains.
The title duke of Normandy was thereafter used by the heir to the throne
until it was replaced by the more well known title Dauphine.
Robert I (Rollo or Gånge-Rolf)
Guillaume I Longue Épée (Longsword)
Robert II, le Diable (the Devil)